Cities as Urban Biodiversity Hotspots - URBIO 2012 presentation (original) (raw)

Biodiversity on the Urban Landscape

This essay, which provides an overview of recent urban biodiversity research, highlights the field’s basic principles by drawing from specific results that have emerged from the Baltimore Ecosystem Study (BES). Because in urban ecosystems, the structure of plant and animal communities are jointly determined by both anthropogenic and natural processes, cities provide an opportune setting to examine general ecological questions concerning community disturbance, patch dynamics, and species invasion. The study of urban habitats also introduces new theoretical questions that are posed by the extreme heterogeneity of the landscape, and the division of land into multiple parcels, each under separate ownership and control. From an applied perspective, urban areas potentially serve as venues for educating the public on the value of biodiversity and for promoting certain species assemblages that are likely to provide ecosystem services and improve the quality of life of nearby human residents. Urban biodiversity researchers face a number of daunting methodological challenges, including (a) the task of integrating community dynamics from the local scale to the regional scale (the metacommunity approach) and (b) clearly isolating evolutionary changes in species that have become adapted to the urban environment.

A global analysis of the impacts of urbanization on bird and plant diversity reveals key anthropogenic drivers

Urbanization contributes to the loss of the world’s biodiversity and the homogenization of its biota. However, comparative studies of urban biodiversity leading to robust generalities of the status and drivers of biodiversity in cities at the global scale are lacking. Here, we compiled the largest global dataset to date of two diverse taxa in cities: birds (54 cities) and plants (110 cities). We found that the majority of urban bird and plant species are native in the world’s cities. Few plants and birds are cosmopolitan, the most common being Columba livia and Poa annua. The density of bird and plant species (the number of species per km2) has declined substantially: only 8% of native bird and 25% of native plant species are currently present compared with estimates of non-urban density of species. The current density of species in cities and the loss in density of species was best explained by anthropogenic features (landcover, city age) rather than by non-anthropogenic factors (geography, climate, topography). As urbanization continues to expand, efforts directed towards the conservation of intact vegetation within urban landscapes could support higher concentrations of both bird and plant species. Despite declines in the density of species, cities still retain endemic native species, thus providing opportunities for regional and global biodiversity conservation, restoration and education.

What evidence exists on the possible effects of urban forms on terrestrial biodiversity in western cities? A systematic map protocol

Environmental Evidence, 2021

Background As urban areas expand, scientists now agree that the city is an important space for biodiversity conservation. Yet, still relatively little is known about how urban forms could have a differential impact on terrestrial species and ecosystems. If some reviews have been conducted to examine the link between biodiversity and urban characteristics at an infra-city scale, none have explored the relationship between urban organization and biodiversity and tried to assess the capacity of various urban forms to maintain and possibly favour flora and fauna in the city. The resulting map will present the state of knowledge regarding possible relationships between urban forms and its features on the establishment and settlement of terrestrial and temperate biodiversity at infra-city scale in western cities. Methods The systematic map will follow the Collaboration for Environmental Evidence (CEE) Guidelines. We will collect the relevant peer-reviewed and grey literature in French and...